Disabled ListItem remains grayed out after enabling

If a ListItem was created disabled, the text on it is grayed out. After enabling it, it becomes clickable but the text is still grayed out.

It happens due to this line in the file ListItemBasic.qml

opacity: enabled ? root.opacity : Style.defaultDisabledOpacity

It should be either 

opacity: enabled ? 1.0 : Style.defaultDisabledOpacity

or something else, because this solution will ignore user's opacity.